Malaria FAQs

Advice on malaria prophylaxis changes frequently.

  • High humidity and temperatures in the range 20-30°C are the optimum conditions for malaria transmission – seasonal rainfall may result in some areas having a variable risk of malaria and urban areas tend to have a lower incidence of malaria than rural areas
  • Malaria transmission is less frequent in regions with temperatures below 16°C or at altitudes greater than 2000m (2500m in some countries)
  • Malaria transmission does not occur in the following countries: Andorra, Australia (including Tasmania), Austria, Belgium, Canada, Czech Republic, Denmark, Finland, France, Germany, Hungary, Italy (including Sardinia), Latvia, Liechtenstein, Lithuania, Luxembourg, Netherlands, New Zealand, Norway, Portugal, Russia, Slovakia, Slovenia, Spain, Sweden, Switzerland, the UK and USA.

Commonly Asked Questions

Advising on malaria prophylaxis

To ensure that correct and consistent advice is given, determination of the following information is important before advising on malaria prophylaxis:

  • Where exactly the traveller is visiting
    • Different areas within the same country can have different chemoprophylaxis requirements – check whether the traveller is planning any day trips or cruises to other areas within the country during their stay and if they are, establish how they are travelling between these areas, for example, overland, by plane or by boat
  • When and for how long the traveller is staying away
    • Malaria risk may vary with season and recommendations should not be given more than six to eight weeks in advance of travel
    • Antimalarial choice may also be subject to licensing restrictions according to the length of stay
  • Whether any other medicines are taken by the traveller or if they have any underlying condition(s) that may affect the choice of regimen, for example, depressive illness, epilepsy, psoriasis or renal impairment
  • Whether any of the travellers are breastfeeding or pregnant
  • Whether any children are travelling and if so, ascertain their weight in kilograms (kg)
    • Many children’s doses of chloroquine and proguanil (which may be sold over the counter) are unlicensed and will require a prescription from a prescriber (see page 8 for further information)
  • For travellers going on a cruise, please contact the NPA Pharmacy Services team for advice


Bite avoidance measures for preventing malaria

The Anopheles mosquito is most active between dusk and dawn and the risk of being bitten is greatest during this time. Other mosquito species are active during the daytime (for example, those that transmit dengue fever, yellow fever and Zika virus). It is, therefore, advisable to practise bite avoidance measures at all times even in malaria-free areas or during the daytime, due to the risk of contracting other insect-borne diseases. All travellers on cruises should use bite avoidance measures when ashore or cruising inland waterways.

Breastfeeding and breastfed infants

  • Prophylaxis is still required in breastfed infants because although antimalarials are excreted in breast milk, the amounts are not sufficient to provide adequate protection
  • Atovaquone/proguanil and doxycycline are contraindicated; however, Public Health England Advisory Committee on Malaria Prevention (ACMP) advise that atovaquone/proguanil may be considered if there is no other suitable antimalarial
  • Mefloquine is excreted into breast milk and the effects are unknown, however may be used as experience suggests it is safe during breastfeeding (off-licence use)
  • Chloroquine and proguanil are considered to be safe, although they may not provide adequate protection for certain areas

Children's doses

Calculate the dose by weight in kg rather than by the age for infants and children. The following doses are based on guidelines from ACMP and may differ from doses in patient information leaflets (PILs)/SPCs (off-licence doses should not be sold, but must be prescribed).


The advice given to travellers going on cruises may vary from advice given to other travellers. This is because most travellers on cruises are only ashore during the daytime when the Anopheles mosquito is not active and thus malaria prophylaxis is not required. However, this is not always the case, and the cruise itinerary must be carefully assessed to determine the risk to malaria.

Cruises in the Caribbean, for example, may include several days travelling along the Amazon basin (Brazil) or the Orinoco river (Venezuela) where the passengers may be ashore or on deck after dusk, and thus at risk of malaria. Similarly, cruises along the coast of East Africa including an overnight stop in Mombasa (Kenya) may also carry a risk of exposure to malaria and require prophylaxis. Overnight stays in other malaria endemic areas may also require malaria prophylaxis.

Insect bite avoidance measures should be used by all travellers on cruises.

For further information, please contact the NPA Pharmacy Services team on 01727 891 800.


Dosage schedule

Antimalarial drugs should be taken with food and swallowed with plenty of water; daily doses should be taken at the same time each day and weekly doses should be taken on the same day of the week. Travellers should be counselled on the importance of completing the course after leaving the endemic area. Mefloquine, doxycycline and atovaquone/proguanil are prescription-only medicines and must not be sold over the counter for malaria prophylaxis under any circumstances.


  • Chloroquine is unsuitable because it can lower the seizure threshold
  • Mefloquine is unsuitable because it increases the risk of seizures and may lower the antiepileptic effect
  • Barbiturates, carbamazepine and phenytoin may reduce the half-life of doxycycline – use a different antimalarial; however, if required, increase dose to 100mg twice a day and advise the patient on how to minimise risk of adverse events

Hepatic or renal impairment

  • All patients should be referred to their specialist to determine the degree of their condition
  • For renal impairment, dosage reduction may be required depending on the severity of renal impairment and the choice of antimalarial


The list below is not exhaustive. The individual Summaries of Product Characteristics (SPCs) should be referred to for further guidance.

Antimalarial Contraindications Precautions for use Possible drug Interactions
  • Patients with hypersensitivity to chloroquine or any excipients in the formulation
  • Patients taking amiodarone
  • Patients with epilepsy (refer to table below for further guidance), glucose-6-phosphate dehydrogenase (G6PD) deficiency, myasthenia gravis, porphyria, psoriasis, and renal or hepatic impairment
  • May cause severe hypoglycaemia and travellers should be advised of the signs and symptoms – treatment review and blood glucose testing may be required in affected individuals
  • Long term therapy may cause irreversible retinal damage and corneal changes
  • Amiodarone
  • Antacids
  • Antiepileptics
  • Anti-infectives which prolong QT interval
  • Antipsychotics
  • Bupropion
  • Ciclosporin
  • Cimetidine
  • Ciprofloxacin
  • Digoxin
  • Halofantrine
  • Hydroxychloroquine
  • Levothyroxine
  • Mefloquine
  • Moxifloxacin
  • Neostigmine and pyridostigmine
  • Omeprazole
  • Praziquantel
  • Pyrimethamine
  • Rabies vaccine
  • Tricyclic antidepressants
  • Children under 12 years of age
  • Patients with:
    • Hypersensitivity to tetracyclines or any excipients listed in individual formulations
    • Fructose intolerance, glucose galactose malabsorption or sucrose-isomaltase insufficiency
    • Pregnancy and breastfeeding – refer to table below for further guidance
  • Patients with renal or hepatic impairment, myasthenia gravis, porphyria and systemic lupus erythromatosus
  • Can cause:
    • Candida overgrowth
    • Photosensitivity – can be minimised by using a broad spectrum sunscreen
    • Oesophagitis if not taken with plenty of fluid and/or if the patient lies down too soon after taking it
  • Alcohol
  • Antacids
  • Barbiturates, carbamazepine, primidone and phenytoin – refer to table below for further guidance
  • Ciclosporin
  • Ergotamine and methysergide
  • Kaolin
  • Methotrexate
  • Methoxyflurane
  • Oral contraceptives
  • Oral typhoid vaccine
  • Penicillin
  • Quinapril
  • Retinoids
  • Rifampicin
  • Sucralfate
  • Warfarin
  • Patients with:
    • Hypersensitivity to quinine, quinidine or to any exicipients in the formulation
    • Severe hepatic impairment
  • Patients with history of:
    • Blackwater fever
    • Psychiatric disorders (including anxiety, depression, psychosis, or schizophrenia)
    • History of seizures (all types) – refer to table below for further guidance
    • Patients taking halofantrine
  • Avoid in those with cardiac conduction disorders and those taking drugs that alter cardiac conduction, including quinine, quinidine and chloroquine
  • For airline pilots and travellers planning to scuba dive, mefloquine is not considered to be the drug of choice
  • It should also be avoided in those taking drugs that lower the seizure threshold (for example, bupropion or tramadol)
  • Patients with eye disorders
  • Mefloquine may induce psychiatric symptoms or cause a change in a patient’s mental state; patients are advised to stop taking mefloquine and seek immediate medical advice if they experience these reactions
  • Anticonvulsants and drugs that lower the seizure threshold (for example, tricyclic antidepressants, selective serotonin reuptake inhibitors, antipsychotics, bupropion, carbamazepine, chloroquine, phenobarbital, phenytoin, tramadol or valproic acid) – refer to table below for further guidance
  • Inhibitors/inducers of CYP3A4 (for example, carbamazepine, phenytoin or rifampicin)
  • Medicines which can prolong the QT interval (for example, anti-arrhythmic drugs, antihistamines, beta blockers, calcium channel blockers, H1-blocking agents, ketoconazole, phenothiazines and tricylic antidepressants)
  • Oral typhoid vaccine
Proguanil and atovaquone/ proguanil
  • Hypersensitivity to the active ingredients or excipients in the formulation
  • Atovaquone/proguanil – in patients with severe renal impairment (creatinine clearance less than 30ml/min)
  • Patients with renal impairment
  • Patients who have vomited within an hour of dosing may need to take a repeat dose of atovaquone/proguanil
  • Patients receiving tetracyclines – parasitemia should be closely monitored as tetracyclines may result in reduction of atovaquone concentrations
  • Patients on warfarin or other coumarin based anticoagulants
  • Antacids and proguanil should be taken at least two to three hours apart
  • Efavirenz or boosted protease-inhibitors
  • Etoposide
  • Metoclopramide
  • Rifabutin and rifampicin
  • Tetracycline
  • Warfarin and related anticoagulants


  • Travel to malarious areas during pregnancy should be avoided as malaria is more severe during pregnancy and there is a higher risk of death compared to non-pregnant women; pregnant travellers must be referred to their doctor
  • If travel is unavoidable, bite avoidance measures must be used and off-licence chemoprophylaxis may be considered
  • Chloroquine and proguanil may be taken in their usual doses in all trimesters of pregnancy
  • Doxycycline is contraindicated during pregnancy, however, under special circumstances may be used providing that the entire course is completed before 15 weeks gestation
  • Mefloquine can be considered in all trimesters for travellers to high risk areas following a careful risk benefit assessment, although caution should be exercised in the first trimester
  • The safety of atovaquone/proguanil in pregnancy has not been established, although it may be considered in the second and third trimesters after a careful risk assessment
  • Pregnant women taking proguanil or atovaquone/proguanil should additionally take 5mg of folic acid daily for at least the first trimester



  • Chloroquine can be used with caution in travellers with mild psoriasis, bearing in mind the possible risk of exacerbation of psoriasis; however it is generally not recommended. Travellers with psoriasis should be considered on an individual basis to determine if the benefit of taking chloroquine for malaria prophylaxis outweighs the risk of exacerbation of psoriasis.
  • Proguanil, mefloquine, doxycycline and atovaquone/proguanil do not cause any problems in travellers with psoriasis.

Special considerations

Please contact the NPA Pharmacy Services team for specific guidance on any of the above special groups and the following patient groups:

  • Patients taking anticoagulants
  • Patients taking hydroxychloroquine
  • Patient with sickle-cell disease or thalassaemia
  • Patients with G6PD deficiency
  • Patients who have had a splenectomy, or those with impaired splenic function
  • Patients with liver disease or renal impairment
  • Patients who are immunosuppressed or have HIV/AIDS

For further information, please contact the NPA Pharmacy Services team on 01727 891 800.

Symptoms of malaria

Patients with the more serious form of malaria (transmitted by the Plasmodium falciparum parasite) can be symptomatic from seven days after being bitten; other forms (transmitted by the Plasmodium vivax and Plasmodium ovale parasites) may incubate for longer. Typical symptoms of malaria are:

  • Fever, chills and sweating – may be cyclical, recurring every 48 hours
  • Myalgia (aching muscles or tenderness)
  • Headache
  • Cough and diarrhoea

Other more severe symptoms include, but are not limited to, acidosis, hypoglycaemia, renal impairment, respiratory distress, shock, and unconsciousness. Travellers are advised to seek medical advice if they experience any of these symptoms within one year and especially within three months of returning from an endemic area.